Process for manufacturing metal compounds



v Patented Sept. 16, 1930 UNITED STATES (PATENT o FFICEI' MAX BUCHNER, HANOVER-KLEEFELD, GERMANY, ASSIGNOR TO ALBERT MEYER- -HOFER, OI ZURICH, SWITZERLAND PROCESS FOR MANUFACTURING METAI: COMPOUNDS No Drawing. Original application filed July 22, 1924, Serial K0. 727,546, and in Germany August 2, 1923. Divided and this application filed. October 23, 1926. Serial No. 143,802.

This'invention relates to a process of manufacturing metal compounds, relying on the reactive and special ability of complex flu- :orine'compounds to decompose.

According'to the new process first a complex fluoride of metal, whose compound is to be formed, is produced. This fluoride is decomposed into its separate fluoride constituents one of which is a sim le fluoride of the metal, and another simple uoride. The metal fluoride is then treated with a compound,

- whose radical it is desired to combine with the metal of the fluoride to form the metal com pound desired, and a resulting fluoride. The

latter is reacted upon with the other fluoride obtained by decomposing the complex fluor ide andin presence of an acid or a salt to reform the starting complex hydrofluoric acid or its salt. The object of the invention is to produce pure chemical compounds in a simple and ready manner from cheap raw-materials, at but small costs.

The followin formulas are illustrative of the reactions s owing the manufacture of soda with the aid of hydrofluosilicic acid.

Sodium 'silicofluorideis produced for instance as follows:

SiF

N a SiF (heated) 2NaF SiF and reacting with calcium carbonate we have The soda is separated by dissolving it.

The reaction ismore ready when working takes place .withsaturated solutions and under pressure, preferably with water not sumcient for di olving-the reacting compounds and while in reducing carbon dioxide. I

From the remaining calcium fluoride :and silicon-fluoride 'the hydrofluosilicic acid is re-formed by the following reaction:

CaF +SiF,+H2SO,=GaS0.+H,SiF, Metal carbonates and the like giving ir the The latter reaction also proceeds without 7 reaction insoluble fluorides are naturally most favorable.

Parallel with the manufacture of soda there can be obtained from N aF by means of 0211- cium sulphide, calcium sulph te and calcium nitrate, the diflicultly obtainable sulphides, sulphites and nitrates of alkali forming metals.

For example, for potassium nitrate the hydrofluosilicic acid may react with potassium chloride. The resulting potassium fluosilicate is decomposed by heat into potassium fluoride and silicon fluoride. The potassium fluoride is converted. into potassium nitrate.

Potassium nitrate can be obtained just as well by means of potassium carbonate and nitric acid, where the potassium carbonate is produced in a manner analogous to the production of soda.

The residues from the above-mentioned reactions, fluor-spar and silicon fluoride, can be converted with acid into hydrofluosilicic acid according to the following formula:

pound is to be formed. Metals or their oxides, carbonatesor other salts can be used as substances that introduce the required posiand decomposed by heating into NaF and fluorideand an alkali metal salt forintroducln the necessary base, in presence of an; acid, t is acld actlng as a eontact'substance.

The following formulas illustrate the procedure: 4

N a SiF (heated) 2NaF SiF; 2NaF+GaCOa=NaCOa+CaF CaF SiF, +2NaGl+ (acid) 7 v "'Na SiF 09,015+ (acid) addition of acid. f

products, alkali earth metal fluoride, silicon The following examples giving weights will illustrate the process.

376 kg. of sodium fluosilicate is heated to 650 C. and splits into 168 kg. of sodium fluoride and 208 kg. of silicon. fluoride- The 168 kg. of sodium fluoride is placed with 221 kg. of basic copper carbonate in 750 liters 0 water and stirred for some time, during which time 203 kg. of copper fluoride separates. The solution contains 106 k of sodium carbonate and 80 kg. of sodium hydroxide.

After separation and washing of the copper fluoride there is added 340 kg. of sodium nitrate dissolved in water, and .acidulated.

. with 12kg. of 63% nitric acid, At a temperature of 80 C. of the mixture the previously separated 208 kg. of silicon fluoride is added. There results 376kg. sodium fluosilicate which is readily filtered and washed from the simultaneously formed copper ni-' trate which amounts to 375 kg.

If the com lex acid is to be formed from the complex uoride, the following will be an example:

188 k sodium fluosilicate is heated to 650 Q. and ecom osed into 84 kg. of sodium fluoride and 104. g. of silicon fluoride. The 84 kg. of sodium fluoride is reacted upon with 303 kg. of lead sulphate in the presence of 570 liters of water at 1202C. and two.atmospheres pressure. The resultant lead fluoride (245 kg.) is separated from the about 20% sodium sul hate liquor.

I then acid with 250 kg. of water and add thereto the 245 kg. of lead fluoride and the previously obtained silicon fluoride. There results 303 k lead sulphate and about 36% hydrofluosi me acid. k

By reacting upon a sodium salt, for instance, sodium chloride, with this hydrofluosilicic acid sodium silicofluoride 1s reproduced, and acid is obtained as by -product.

It is of advantage, to carry out the reaction between a salt and a complex fluoric acid with a solid salt.

An example for the production of soda is:

84 kg. fluoride of sodium and 100 kg. calclum carbonate are poured into 350 liters of water and agitated for some hours, until the reaction is complete. When the reaction is from the cyclic process, which latter is put directly into the hydrochloric acid solution. The sodium fluosilicate is decomposed by ilute 100 kg. of 98% sulphuric into potassium fluoride and boron fluoride.

The potassium fluoride is then reacted upon with an insoluble carbonate, as calcium carbonate, to form insoluble calcium fluoride and potash (K CO in the presence of. water,

not suflicie'nt' to dissolve the resulting carbonates. The precipitate is filtered oil and washed with water. The boron fluoride re sulting from the} decomposition of the potassium borofluoride, is' converted into potassium borofluoride by means of hydrochloric acid that contains the calcium fluoride resulting from the final reaction as well as the necessary amountof potassium chloride.

I claim:

1. A process for manufacturing metal compounds consisting in first forming a complex fluoride of a metal whose compound is to be formed, decomposing the latter into its separate fluoride constituents one of which is a simple fluoride of the metal, and another simv ple fluoride, treating the metal fluoride with a compound whose non-metallic radical is to be bound to the metal of the fluoride to form the metal compound desired, and a resulting fluoride, reacting upon the resulting fluoride and said other fluoride with an acid to reform the complexhydrofluoric acid.

2. A process for manufacutring metal com-- pounds consisting in first forming a complex fluoride of a metal whose compound is to be formed, decomposing the latter into its separate fluoride constituents one of which is a simple fluoride of the metal, and another simple fluoride, treating the metal fluoride with a compound whose non-metallic radical it is to be bound to the metal of the fluoride to form the metal compound desired, and a resulting fluoride, reactin upon the resulting fluoride and said other to re-form the complex hydrofluoric acid, that is converted with a salt oisuch metal, whose compound is to be formed into a comple fluoride and an acid as byproduct.

3. In a process for manufacturing metal compounds from a complex fluoride of' a metal whose compound is to :be produced, de-

composing this complex fluoride by heat into a fluoride of the metal and another fluoride,

oride, reacting upon the resulting fluoride uoride with an acid and said other fluoride with a salt to the starting complex fluoride.

4. In a process for manufacturing metal compounds from a complex fluoride of a metal whose compound is to be produced, decomposing this complex fluoride by heat into a fluoride of the metal and another fluoride, reacting upon the metal fluoride with a compound whose non-metallic radical is to be bound to the metal of the fluoride to form the desired metal of the fluoride compound and a resulting fluoride, reactingu on the resulting fluoride and said other uoride with a salt in the presence of an acid to produce the starting complex fluoride.

5. In a process for manufacturing metal compounds, first forming a complex fluoride of a metal whose compound is to be formed, decomposing the latter into its separate fluoride constituents one of which is a simple fluoride of the metal and another simple fluoride, treating the metal fluoride with a salt of the acid which is desired to combine with the metal to form the metal compound desired, and a resultin fluoride, and reacting upon the resulting fluoride and said other fluoride with an acid to re-form the complex hydro-fluoric acid.

6. In a process for manufacturing metal compounds from a complex fluoride of a metal whose compound is to be produced, decomposing this complex fluoride by heat into a fluoride of the metal and another fluoride, reacting upon the metal fluoride with a salt of the acid which is to be bound to the metal of the fluoride to form the desired metal compound and a resulting, fluoride, and reacting upon the resulting fluoride and said other fluoride with a salt in the presence of an acid to produce, the starting complex fluoride.

produce 7. The process of forming metal com-- 8. The process of forming metal compounds, which comprises, react-in upon al-- kali metal salts with a complex uoric acid to form a complex alkali metal fluoride and an acid, decomposing the complex fluoride into a simple alkali metal fluoride and another simple fluoride, reacting on the alkali metal fluoride with a com ound containing a radical it is desired to unite with the alkali metal of said metal fluoride, and forming an alkali metal salt and a second fluoride, reacting upon said second fluoride and said other fluoride with an alkali metal salt in the presence of an acid to re-form the complex alkali metal fluoride. g

9. The process of forming metal compounds, Which comprises reactin upon an alkali metal salt with a complex uoric acid to form a complex alkali metal fluoride and an acid, decomposing the complex alkali metal fluoride into a simple alkaline metal fluoride and another fluoride, converting the alkali metal fluoride by another metal compound into an alkali metal salt and a resulting fluoride in the presence of a solvent for the alkali metal salt obtained the quantity of said solvent being insuflicient to dissolve the whole of the alkali metal salt formed, and converting the resulting fluoride and said other fluoride into the starting complex compound.

10. The process of producing metal compounds, which comprises reacting upon an alkali metal salt with a complex fluoric acid, decomposing the resulting alkali metal complex fluoride into a simple alkali metal fluoride and another fluoride, reacting upon the latter alkali metal fluoride with a carbonate in the presence of carbon di-oxide to form alkali metal carbonate and a resulting fluoride, and converting said resulting and other fluoride into the starting complex fluor de.

In testimony that I claim the foregoing as my invention, I have si ned m name.

DR. AX B CHNER. 

